I tried modifying Makefile. (look for uim-xim line) changed those lib64 to lib32. Saw weak definition but I seemed to be able to compile. Am very sleepy/ Will try tomorrow. // Still trying... could compile uim-xim but I get errors after that. Apparently I do not seem to be able to solve this problem.

I got another reply from Japan. Mr. Tokunaga kindly made a patch for a problem I encountered right after the LDFLAGS problem. The result was ... completed compilation of uim with neko_gnome2. Here is a brief summary.

This also shows that their configure script needs fixing. It needs to stop when requirements are not met, not keep going.
As whiter mentions you need libiconv installed, and it needs to be found by configure of course...